Apparatus for altering the length of synthetic strands

ABSTRACT

Apparatus for altering the length of a synthetic fiber strand, in the form of a continuous filament or yarn, by stretching or shrinking the same. The apparatus comprises a first strand feeding means having a driven feed roll means and a separator idler roller; a first heating means in the form of a heated roll means coaxial with said feed roll means and a separator idler roller; a second heating means in the form of a heated plate over which the strand slides; a second feeding means in the form of a driven roller and a separator idler roller; and a driven take-up spool. The strand passes around the first feed roll means and its separator idler roller and then around the heated roll means and its separator idler roller. The strand then passes around the driven roller and separator idler roller of the second feeding means, and then to the take-up spool. The second feeding means is driven faster or slower than the first feeding means depending on whether the strand is to be stretched or shrunk. The first feed roll means and the heated roll means may be of the same diameter, or they may be of different diameters if it is desired to prestretch or pre-shrink the strand prior to the stretching or shrinking which occurs between the first and second feeding means. The coaxial feeding and heating roll means may be integral, they may be separate rollers rigidly connected together, or the heated roller may be an idler roller driven only by the strand.

United States Patent 1 Bucher I APPARATUS FOR ALTERING THE LENGTH OF SYNTHETIC STRANDS [75] Inventor: Erich Bucher, Goppingen, Germany [73] Assignee: Zinser-Textilmaschinen GmbH,

Ebersbach, Germany 1 Filed: Mar. 5, 1973 21 Appl. No.: 338,300

[30] Foreign Application Priority Data Mar. 3, 1972 Germany 2210272 [52] US. Cl. 28/713; 57/555; 425/66 [51] Int. Cl. D02] I/22 [58] Field of Search 28/713; 425/66; 57/555 [56] References Cited UNITED STATES PATENTS 2,988,866 6/1961 Kleekamm et a1 28/713 X 3,028,653 4/1962 Evans 28/7l.3 X

3,159,964 12/1964 Kretsch 28/71.3 X 3,409,958 11/1968 Bucher et a1. 28/713 3.420.983 1/1969 McCardet a1... 28/713 X 3,471,608 10/1969 Schippers i 28/713 X 3,518,822 7/1970 McCard 28/713 X 3,608,299 9/1971 Dugas v 28/713 UX 3,732,395 5/1973 David 28/713 UX FOREIGN PATENTS OR APPLICATIONS 1,194,016 5/1959 France 28/713 810,922 3/1959 United Kingdom 28/713 699,274 12/1965 Italy 28/713 1 Nov. 18, 1975 Primarr Examiner-Robert R. Mackey Attorney, Agent, or Firm-Edwin E. Greigg [57] ABSTRACT Apparatus for altering the length of a synthetic fiber strand, in the form of a continuous filament or yarn, by stretching or shrinking the same. The apparatus comprises a first strand feeding means having a driven feed roll means and a separator idler roller; a first heating means in the form of a heated roll means coaxial with said feed roll means and a separator idler roller; a second heating means in the form of a heated plate over which the strand slides; a second feeding means in the form of a driven roller and a separator idler roller; and a driven take-up spool. The strand passes around the first feed roll means and its separator idler roller and then around the heated roll means and its separator idler roller. The strand then passes around the driven roller and separator idler roller of the second feeding means, and then to the take-up spool. The second feeding means is driven faster or slower than the first feeding means depending on whether the strand is to be stretched or shrunk. The first feed roll means and the heated roll means may be of the same diameter, or they may be of different diameters if it is desired to pre-stretch or pre-shrink the strand prior to the stretching or shrinking which occurs between the first and second feeding means. The coaxial feeding and heating roll means may be integral, they may be separate rollers rigidly connected together, or the heated roller may be an idler roller driven only by the strand.

7 Claims, 8'Drawing Figures US. Patsnt Npv.18,1975 Sheet1of3 3,919,748

US. Patent Nov. 18, 1975 Sheet 2 of3 3,919,748

FIGB

S. Patent Nov. 18,1975 Sheet30f3 3,919,748

APPARATUS FOR ALTERING THE LENGTH OF SYNTHETIC STRANDS The invention concerns apparatus for altering the length, by stretching or shrinking, of a synthetic fiber strand, either a continuous filament or yarn, wherein the strand is heated first by a rotating heated cylinder or roll means on which the strand is carried without slipping and then by a second heated unit which is located at a distance from the heated cylinder. The total amount of stretching or shrinking of the strand is caused by two continuously driven unheated roller feed mechanisms of which the first precedes the heated cylinder or roll means and includes a first driven feed roll means whereas the other roller feed mechanism is located following the second heating unit.

In known apparatus of this kind a heated cylinder is used and is located in the space between the first roller feed mechanism and the second heating unit at some distance from the latter. One disadvantage among others in this case is the structural requirement necessitated by the separate heated cylinder and its disposition within the mechanism and also the large distance between the first and second roller feed mechanisms resulting from this disposition because of which the structural height of machines comprising such installations is increased.

It is an aim of this invention therefore to decrease the structural and space requirements of such installations.

According to the invention it is intended for this purpose in a machine of the kind described above that the heated roll means be disposed side-by-side with the first feed roll means and that it be structurally connected thereto.

Because of this arrangement of the heated cylinder or roll means and its structural connection with the driven feed roll means of the first feed roll mechanism, only a single swing arm is required for the support of both roll means on the machine and considerable space is saved. Because of the structural union of these two roll means the path of the strand from the first feed roller mecha nism to the heated cylinder or roll means is more precise than in known installations of this kind and because of the structural simplification the operational security is increased and operating costs are lowered.

Preferably the heated cylinder or roll means and the first feed roll means are rigidly connected and are coaxial. Thus both roll means have the same rotational cording to the requirements one can provide that both roll means advance the strand with exactly the same speed by giving them exactly the same diameter or one can provide that the strand is fed faster or slower by the heated cylinder or roll means than by the first feed roll means in order to produce a shrinking or a pre-stretching without slippage and this is done by making the diameter of these two roll means correspondingly different. It is particularly suitable to provide a pre-stretching i.e., to make the diameter of the heated cylinder larger than that of the first feed roll means. If one wishes to provide that the heated roll means is not itself driven but rather is turned by the strand around it. this can easily be accomplished by letting it turn freely on an axle common to both roll means. The Figures show preferred exemplary embodiments of the invention.

FIG. 1 shows a stretch or shrink installation according to a first exemplary embodiment of the invention in schematic representation where all elements not necessary for the understanding of this installation have been left out;

FIG. 2 shows the first feed roll means and the heated cylinder or roll means of FIG. 1 together with the main drive roller or shaft in partly sectional representation as seen in the direction of arrow A of FIG. 1.

FIGS. 3, 4 and 5 each show a modification of FIG. 2.

FIG. 6 shows a futher modification of FIG. 2 in enlarged unsectioned representation.

FIG. 7 shows a. section through the roller shown in FIG. 6, and

FIG. 8 shows a twin arrangement of feed and heated rollers. i

In the drawings corresponding parts have the same reference numerals.

FIG. 1 shows a schematic representation of a side view of a stretching or shrinking installation 9 for synthetic strands as a part of a machine which is not shown in detail, this machine having a plurality of such installations on each side. This installation comprises a first feed roller mechanism 11, a first heating mechanism formed by heated cylinder or roll means 20, a second heating unit formed as a heated plate 12, a second feed roller mechanism 13, and a take-up mechanism for the windingof the stretched or shrunken strand. The first feed roller mechanism 1 1 includes the enlarged section 15 of a main drive roller or shaft 16 which extends over the length of the respective side of the machine. This main drive roller 16 drives all first feed roll means on the respective side of the machine such as roll means 17 which has an associated separator roller 19. A further separator roller 21 serves for the placing of strand 22 on heated roll means 20. Such separator rollers 19 and 21 are always required in installations of the present kind in order to effect a slip-free feeding of the strand by a multiple mutual grouping of the respective driven roll means and of the separator roller. Separator rollers are freely turning and are turned by the strand. The first feed roll means 17 is journalled on a stud 23 which also carries heating unit 24 of heated roll means 20. This stud 23 is fixedly connected to swinging arm 26 hinged from the machine frame 10 and loaded by a compression spring 25.

Swing arm 26 presses the first feed roll means 17 and its elastic plastic cover 27 onto the section 15 of the main drive roller 16 which drives it.

The second feed mechanism 13 shows a driven roller 28 and its corresponding separator roller 29. The driven roller 28 can be a cylinder or also a section of a second main drive roller or shaft extending over the side of the machine. The take-up mechanism 14 can be of any suitable construction; here it is a driven spool.

The first feed roll means 17 has a roller bearing whose inner race is fixed on stud 23 of swing arm 26 and whose outer race is integral with coaxial heated roll means 20. On the outer race of this roller bearing is located plastic cover 27. The heated cylinder or roll means is made of metal. In its interior is positioned the stationary electrical heating unit 24 which heats it from within.

The second heating unit 12 consists of a customary heated plate 12 over whose slightly convex surface strand 22 slides. This plate has a higher surface temperature than has heating cylinder or roll means 20. The first and second feed means 17 and 28 have differing peripheral speeds in order to. achieve the total desired stretching or total shrinking. The first feed roll means 17 in this exemplary embodiment has a larger diameter than has heating cylinder or roll means 20; thus a shrinking of strand 22 has between the primary transport roll means 17 and the heated roll means 20, which also transports the strand without slipping, is achieved. The diameter of the heating cylinder or roll means 20 can according to the requirement however, be equal to that of feed roll means 17 or be larger. The strand is pinched between the main driving roller 16 and the first feed roll means 17.

In the embodiment of FIG. 3 the main driving roller 16' has a constant diameter throughout its length whereas in FIG. 2 that part of the main driving roller 16 which drives the first feed roll means 17 has a larger diameter than the contiguous sections of this roller. The first feed roll means 17 and the heated roll means 20 could correspond to the respective roll means of FIG. 2.

In the embodiment of FIG. 4 the heated roller 20 has the same diameter as the first feed roller 17. The heated roller turns freely on stud 23 of the swinging arm 26 and is turned only by the fiber which loops it so that only roller 17 is driven by the main driving roller 16.

In the embodiment of FIG. 5 the first roller 17 is completely metallic and is pressed against an elastic plastic ring 30 which itself is fixedly disposed on the main driving roller 16". The diameter of heating roller 20 fixedly connected to roller 17 is somewhat smaller in this exemplary embodiment than the diameter of the feed roller. Roller 17 has a collar 31 intended to prevent possible sliding off of the strand winding around it onto the heating roller 20.

FIGS. 6 and 7 show a modification of FIG. 2 in enlarged version where a separator roller 19' is disposed on an upwardly extending portion 34 of swinging arm 26. First feed roll means 17" has an elastic cover 27 of heat-resistant plastic which is laid into a metallic cartridge 35 mounted on roller bearings. To the first feed roll means 17" is connected directly the metallic heated roll means 20 having an elastic cover 27 and having the idential diameter as feed roll means 17". The interior of heated roll means 20 contains the heating unit 24 which is rigidly mounted on the stud 23 of swinging arm 26 and is supplied by an electrical conduit 36. Swinging arm 26 also carries thread guide 37 which displaces strand 22 in such a way that during its transfer from the first feed roll means 17 to the heating unit 20 it always arrives securely at some distance from the feed roll means 17''. The separator roller 19 guides the strand onto both roll means 17 and 20.

In the embodiment of FIG. 8 there is shown a twin roller installation 40 which comprises two first feed rollers l7 and two heated rollers 20. The two feed rollers 17 together with their respective heated rollers 20 rigidly connected thereto are assigned to two adjacent installations for the stretching or shrinking of synthetic strands. Both primary transport rollers 17 and heating rollers 20 are driven by a common coaxial intermediate roller 42 which is connected to them to turn in unison therewith. This intermediate roller 42 is driven by the main driving roller 16" by pressing against the plastic cover 30 of this main driving roller. Whereas in the exemplary embodiments of FIGS. 1 through 7 the first feed roller was always frictionally driven directly by the main driving roller and therefore the strand which looped it was pinched between it and the main driving roller; instead, in FIG. 8 there exists an air gap between the first feed roller and the main driving roller so that the threads looping the first feed rollers are not pinched. In all exemplary embodiments there is an air gap between the heating rollers and the main driving rollers. Also, to ensure secure slip-freefeeding of the strand, the first feed roller and the heating roller are each looped several times by the strand where the displacement of these loops can be effected by means of one or two separator rollers.

The expressions feeding roll means" and heated roll means as used in the specification and claims are intended to be generic to all modifications. While there are separate rolls or rollers 17 and 20 in FIG. 4, this is not true of the modifications of FIGS. 2, 3, 6 and 7. The expression roll means" is considered equally applicable to separate rollers or to separate portions of a single roller.

What is claimed is:

1. Apparatus for altering the length of a synthetic strand comprising, in combination:

a first strand feeding means including a driven, un-

heated roll means 17 or 17' or 17") around which the strand is to be first wound;

a first heating means including a heated roll means (20 or 20) rigidly connected to said unheated roll means and having a diameter different from that of said unheated roll means and around which the strand is to be wound immediately after passing from said first strand feeding means, said first heating means being laterally adjacent to and coaxial with said driven roll means and rigidly connected thereto so as to be driven at exactly the same r.p.m. as said driven roll means;

a second heating means (12), over which the strand is to pass subsequent to its passage from said first heating means, said second heating means being spaced a substantial distance from said first heating means;

a second strand feeding means including a driven roller (28) around which said strand is to be wound;

said first and second strand feeding means being continuously driven at different peripheral speeds to effect alteration in the length of said strand.

2. Apparatus according to claim 1 in which there is a driving roller (16 or 16' or 16) for driving said driven roll means; a pivotally mounted spring-loaded arm (26) for supporting said driven roll means and for pressing it into driving relation with said driving roller; and said heated roll means being spaced from said driving roller a distance greater than the diameter of said strand.

3. Apparatus according to claim 1 in which the diameter of the driven roll means is greater than the diameter of the heated roll means.

4. Apparatus according to claim 1 in which the driven roll means and the heated roll means are immediately adjacent to each other.

5. Apparatus according to claim 1 in which there is a separator idler roller (19) common to said driven roll means and said heated roll means and spaced therefrom and around which the strand is wound.

6. Apparatus according to claim 1 in which there is a main driving roller (16') parallel to said driven roll means; an intermediate roller (42) coaxial with and rigidly connected to said driven roll means and normally in driving engagement with said main driving roller, said driven roll means and said heated roll means being on each side of said intermediate roller (42), said driven roll means each being rigidly connected to said intermediate roller to rotate in unison therewith. 

1. Apparatus for altering the length of a synthetic strand comprising, in combination: a first strand feeding means including a driven, unheated roll means (17 or 17'' or 17'''') around which the strand is to be first wound; a first heating means including a heated roll means (20 or 20'') rigidly connected to said unheated roll means and having a diameter different from that of said unheated roll means and around which the strand is to be wound immediately after passing from said first strand feeding means, said first heating means being laterally adjacent to and coaxial with said driven roll means and rigidly connected thereto so as to be driven at exactly the same r.p.m. as said driven roll means; a second heating means (12), over which the strand is to pass subsequent to its passage from said first heating means, said second heating means being spaced a substantial distance from said first heating means; a second strand feeding means including a driven roller (28) around which said strand is to be wound; said first and second strand feeding means being continuously driven at different peripheral speeds to effect alteration in the length of said strand.
 2. Apparatus according to claim 1 in which there is a driving roller (16 or 16'' or 16'''') for driving said driven roll means; a pivotally mounted spring-loaded arm (26) for supporting said driven roll means and for pressing it into driving relation with said driving roller; and said heated roll means being spaced from said driving roller a distance greater than the diameter of said strand.
 3. Apparatus according to claim 1 in which the diameter of the driven roll means is greater than the diameter of the heated roll means.
 4. Apparatus according to claim 1 in which the driven roll means and the heated roll means are immediately adjacent to each other.
 5. Apparatus according to claim 1 in which there is a separator idler roller (19'') common to said driven roll means and said heated roll means and spaced therefrom and around which the strand is wound.
 6. Apparatus according to claiM 1 in which there is a main driving roller (16'') parallel to said driven roll means; an intermediate roller (42) coaxial with and rigidly connected to said driven roll means and normally in driving engagement with said main driving roller, said driven roll means and said heated roll means being spaced from said driving roller a distance greater than the diameter of said strand.
 7. Apparatus according to claim 6 in which there is a driven roll means (17'') and a heated roll means (20) on each side of said intermediate roller (42), said driven roll means each being rigidly connected to said intermediate roller to rotate in unison therewith. 